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Strings in a 2-d Extremal Black Hole

Amit Giveon·Amit Sever
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Abstract

String theory on 2-d charged black holes corresponding to (SL(2)xU(1)_L)/U(1) exact asymmetric quotient CFTs are investigated. These backgrounds can be embedded, in particular, in a two dimensional heterotic string. In the extremal case, the quotient CFT description captures the near horizon physics, and is equivalent to strings in AdS_2 with a gauge field. Such string vacua possess an infinite space-time Virasoro symmetry, and hence enhancement of global space-time Lie symmetries to affine symmetries, in agreement with the conjectured AdS_2/CFT_1 correspondence. We argue that the entropy of these 2-d black holes in string theory is compatible with semi-classical results, and show that in perturbative computations part of an incoming flux is absorbed by the black hole. Moreover, on the way we find evidence that the 2-d heterotic string is closely related to the N=(2,1) string, and conjecture that they are dual.

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Amit Giveon, Amit Sever. 2005-01-05. Strings in a 2-d Extremal Black Hole. https://doi.org/10.1088/1126-6708%2F2005%2F02%2F065

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